A firefight in the Jenin refugee camp which resulted in the deaths of three Palestinians has raised fears of renewed anarchy in the West Bank.

A joint force of IDF soldiers and the elite police anti-terror unit entered the camp in the early hours of Saturday morning. They acted following information that reached the Shin Bet that Hamze abu Alhija, a known Hamas militant, was planning an attack on an Israeli target.

Alhija, alerted in his home, opened fire and was killed in the ensuing gunfight. Two other Palestinian militants, identified as members of Islamic Jihad, were also killed. Seven other Palestinians and two Israeli police officers were injured.

An IDF spokesman said the three Palestinians had been killed while trying to shoot and throw explosive charges at the Israeli forces.

But Palestinian witnesses claimed that Alhija was trying to surrender, and that his two friends were shot while removing his body.

Subsequent violent demonstrations around Jenin ended after 24 hours, but the incident intensified concern within the Israeli defence establishment that the Palestinian Authority is making less of an effort to curb activities of Islamist groups in the West Bank.

While there has been an increase of low-level violence over the past two years, the return of organised Hamas and Jihad cells to the West Bank is relatively recent.

Fatah-dominated security forces have acted ruthlessly against their Palestinian rivals in the past, but now Israeli officers are discerning a lack of motivation on the Palestinian side to continue challenging the militants.